This project proposes COPE, a new architecture for wireless mesh networks. In addition to forwarding packets, routers mix (i.e., code) packets from different sources to increase the information content of each transmission. We show that intelligently mixing packets increases network throughput. Our design is rooted in the theory of network coding. Prior work on network coding is mainly theoretical and focuses on multicast traffic. This paper aims to bridge theory with practice; it addresses the common case of unicast traffic, dynamic and potentially bursty flows, and practical issues facing the integration of network coding in the current network stack. We evaluate our design on a 20-node wireless network, and discuss the results of the first testbed deployment of wireless network coding. The results show that COPE largely increases network throughput. The gains vary from a few percent to several folds depending on the traffic pattern, congestion level, and transport protocol.

XORs In The Air: Practical Wireless Network Coding,
Sachin Katti, Hariharan Rahul, Wenjun Hu, Dina Katabi, Muriel Medard, and Jon Crowcroft
IEEE/ACM Transaction on Networking, 2008. IEEE Communication Society William Bennett Prize. PDF

Real and Complex Network Codes: Promises and Challenges,
S. Shintre, S. Katti, S. Jaggi, B. K. Dey, D. Katabi, and M. Medard
Allerton, 2008. PDF

MIXIT: The Network Meets the Wireless Channel.
Sachin Katti and Dina Katabi,
HotNets, 2007. PDF

Wireless Network Coding: Opportunities and Challenges.
Christina Fragouli, Dina Katabi, Athina Markopoulou, Muriel Medard, and Hariharan Rahul,
MILCOM, 2007. PDF

Resilient Network Coding In The Presence of Byzantine Adversaries,
Sid Jaggi, Michael Langberg, Sachin Katti, Tracy Ho, Dina Katabi, and Muriel Medard,
IEEE INFOCOM, 2007. PDF

Real Network Codes: Breaking the All-Or-Nothing Barrier
Sachin Katti, Saurabh Shintre, Sid Jaggi, Dina Katabi, Muriel Medard,
Allerton, 2007 PDF

XORs In The Air: Practical Wireless Network Coding,
Sachin Katti, Hariharan Rahul, Wenjun Hu, Dina Katabi, Muriel Medard, and Jon Crowcroft,
ACM SIGCOMM, 2006. PDF

The Importance of Being Opportunistic: Practical Network Coding For Wireless Environments,
Sachin Katti, Dina Katabi, Wenjun Hu, Hariharan Rahul, and Muriel Medard,
Allerton, 2005.PDF

Sachin Katti
Stanford University

Dina Katabi
Massachusetts Institute of Technology

Hariharan Rahul
Massachusetts Institute of Technology

Muriel Medard
Massachusetts Institute of Technology

Wenjun Hu
University of Cambridge

Jon Crowcroft
University of Cambridge